nextcloud/lib/private/encryption/keys/storage.php

232 lines
5.7 KiB
PHP
Raw Normal View History

<?php
/**
* ownCloud
*
* @copyright (C) 2015 ownCloud, Inc.
*
* @author Bjoern Schiessle <schiessle@owncloud.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
* License as published by the Free Software Foundation; either
* version 3 of the License, or any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU AFFERO GENERAL PUBLIC LICENSE for more details.
*
* You should have received a copy of the GNU Affero General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*/
namespace OC\Encryption\Keys;
use OC\Encryption\Util;
use OC\Files\View;
use OCA\Files_Encryption\Exception\EncryptionException;
class Storage implements \OCP\Encryption\Keys\IStorage {
/** @var View */
private $view;
/** @var Util */
private $util;
// base dir where all the file related keys are stored
private $keys_base_dir;
private $encryption_base_dir;
private $keyCache = array();
/** @var string */
private $encryptionModuleId;
/**
* @param string $encryptionModuleId
* @param View $view
* @param Util $util
*/
public function __construct($encryptionModuleId, View $view, Util $util) {
$this->view = $view;
$this->util = $util;
$this->encryptionModuleId = $encryptionModuleId;
$this->encryption_base_dir = '/files_encryption';
$this->keys_base_dir = $this->encryption_base_dir .'/keys';
}
/**
* get user specific key
*
* @param string $uid ID if the user for whom we want the key
* @param string $keyId id of the key
*
* @return mixed key
*/
public function getUserKey($uid, $keyId) {
2015-03-17 15:11:38 +03:00
$path = '/' . $uid . $this->encryption_base_dir . '/'
. $this->encryptionModuleId . '/' . $uid . '.' . $keyId;
return $this->getKey($path);
}
/**
* get file specific key
*
* @param string $path path to file
* @param string $keyId id of the key
*
* @return mixed key
*/
public function getFileKey($path, $keyId) {
$keyDir = $this->getFileKeyDir($path);
return $this->getKey($keyDir . $keyId);
}
/**
* get system-wide encryption keys not related to a specific user,
* e.g something like a key for public link shares
*
* @param string $keyId id of the key
*
* @return mixed key
*/
public function getSystemUserKey($keyId) {
2015-03-17 15:11:38 +03:00
$path = $this->encryption_base_dir . '/' . $this->encryptionModuleId . '/' . $keyId;
return $this->getKey($path);
}
/**
* set user specific key
*
* @param string $uid ID if the user for whom we want the key
* @param string $keyId id of the key
* @param mixed $key
*/
public function setUserKey($uid, $keyId, $key) {
2015-03-17 15:11:38 +03:00
$path = '/' . $uid . $this->encryption_base_dir . '/'
. $this->encryptionModuleId . '/' . $uid . '.' . $keyId;
return $this->setKey($path, $key);
}
/**
* set file specific key
*
* @param string $path path to file
* @param string $keyId id of the key
2015-03-17 15:11:38 +03:00
* @param mixed $key
*/
public function setFileKey($path, $keyId, $key) {
$keyDir = $this->getFileKeyDir($path);
return $this->setKey($keyDir . $keyId, $key);
}
/**
* set system-wide encryption keys not related to a specific user,
* e.g something like a key for public link shares
*
* @param string $keyId id of the key
* @param mixed $key
*
* @return mixed key
*/
public function setSystemUserKey($keyId, $key) {
2015-03-17 15:11:38 +03:00
$path = $this->encryption_base_dir . '/'
. $this->encryptionModuleId . '/' . $keyId;
return $this->setKey($path, $key);
}
/**
* read key from hard disk
*
* @param string $path to key
* @return string
*/
private function getKey($path) {
$key = '';
if ($this->view->file_exists($path)) {
if (isset($this->keyCache[$path])) {
$key = $this->keyCache[$path];
} else {
$key = $this->view->file_get_contents($path);
$this->keyCache[$path] = $key;
}
}
return $key;
}
/**
* write key to disk
*
*
* @param string $path path to key directory
* @param string $key key
* @return bool
*/
private function setKey($path, $key) {
$this->keySetPreparation(dirname($path));
$result = $this->view->file_put_contents($path, $key);
if (is_int($result) && $result > 0) {
$this->keyCache[$path] = $key;
return true;
}
return false;
}
/**
* get path to key folder for a given file
*
* @param string $path path to the file, relative to data/
* @return string
* @throws EncryptionException
* @internal param string $keyId
*/
private function getFileKeyDir($path) {
if ($this->view->is_dir($path)) {
throw new EncryptionException('file was expected but directory was given', EncryptionException::GENERIC);
}
list($owner, $filename) = $this->util->getUidAndFilename($path);
$filename = $this->util->stripPartialFileExtension($filename);
// in case of system wide mount points the keys are stored directly in the data directory
if ($this->util->isSystemWideMountPoint($filename)) {
$keyPath = $this->keys_base_dir . $filename . '/';
} else {
$keyPath = '/' . $owner . $this->keys_base_dir . $filename . '/';
}
return \OC\Files\Filesystem::normalizePath($keyPath . $this->encryptionModuleId . '/', false);
}
/**
* Make preparations to filesystem for saving a keyfile
*
* @param string $path relative to the views root
*/
protected function keySetPreparation($path) {
// If the file resides within a subdirectory, create it
if (!$this->view->file_exists($path)) {
$sub_dirs = explode('/', $path);
$dir = '';
foreach ($sub_dirs as $sub_dir) {
$dir .= '/' . $sub_dir;
if (!$this->view->is_dir($dir)) {
$this->view->mkdir($dir);
}
}
}
}
}